Pneumatic key-striker for mechanical musical instruments.



N0. 686,682. Patented Nov..l2, |90l.' H. M. SALYEB.

PNEUMATIC KEY STBIKER FUR MECHANICAL MUSICAL INSTRUMENTS.

A i ucmon filed July 7, 1900 (No Model.)

WITNESSES: INVENTOR Z 1' 42 7102? 7 I I I, Way? m ATTORNEY UNITED STATESPATENT OFFICE.

HARRY M. SALYER, OF-NElV YORK, N. Y., ASSIGNOR TO THE FIRM OF LUDVVIGAND COMPANY, OF BOROUGH OF BRONX, NEW YORK, N. Y.

PNEUMATIC KEY-STRIKER FOR MECHANICAL MUSICAL INSTRUMENTS.

SPEGIFIGATION forming part of Letters Patent N 0. 686,682, datedNovember 12, 1901.

Application filed July 7, 1900.

T0 to whom it may concern.-

Be it known that I, HARRY M. SALYER, a citizen of the United States, anda resident of the city of New York, borough of the Bronx, in the countyof New York and State of New York, have invented certain new and usefulImprovements in Pneumatic Key-Strikers for Mechanical MusicalInstruments, of which the following is a specification.

This invention relates to improvements in self-playing attachments forkey musical instruments, and especially to a new and improved pneumaticmechanism for actuating the keys.

The object of my invention is to provide a new and improved pneumatickey-operating mechanism which is simple in construction, reliable,positive, and quick in action, and readily controlled.

In the accompanying drawing, forming a part of this specification, avertical longitudinal sectional view of myimproved pneumatickey-operating mechanism is shown, the COD.

trolling-sheet being shown in diagram.

The compressed-air chamber A is charged with compressed air in anysuitable manner and at-any desired degree of compression. It is broughtinto communication with a valvecasing B by means of the opening B, ofany desired shape, and with this valve-casing one end of a cylinder O isconnected, which cylinder is brought in communication with the casing Bby the opening 0. The cylinder 0 contains a piston D, having a suit-ablepacking and attached to the inner end of a pistonrod D, which is guidedin an aperture in the outer head 0 of the cylinder, which head has ahole 0 for the escape and admission of air. A helical spring D surroundsthe piston-rod D between the piston D and. the head C- and presses thepiston upward. A key-striking head E, having a felt or rubber pad E, isattached to the outer end of the piston-rod D.

The valve-casing B contains a fixed hub F, provided with a central boreF, extending in the direction of the length of the casing andtransversely to the axis of the cylinder 0. A duct G extends from thebore F to the hole 0, and a passage or duct H extends from the duct oropening B to one end of the hub F. A piston-valve J, fitting in thecasing 13, is

Serial No. 22.775. (No model.)

I attached to a tubular rod J, passing loosely through the bore F of thehub F, and this piston-valve is provided with a washer-plate J which isadapted to seat on that end of the hub at which the d not H terminates.A ventpassage K extends from the under side of the piston-valve J atthat part of the rim at which the d not H terminates to the bore of thetubular piston-rod J, which vent-passage K can be controlled by avalve-screw L, screwed in to the tubular rod J and projecting from oneend of the same. The piston-valve J is pressed by a spring M upon itsseat on the hub F, which spring is interposed between the piston J andthe head N of the valve-casing. A valve 0, having a suitablepacking-disk O, is secured on the rod J and is adapted to seat 011 thatend of the hub F opposite the one on which the piston-valve J seats.Avent-pipe extends from the head N of the valve-casing B to a bridge Q,where it can be closed by a spring-pressed valve R when said valve ispressed down by a slotted or other note-sheet S passing over it. When aslot or recess S in the note-sheet arrives at the nose R of the valve,the latter is pressed up by its spring and the end of the vent-passage Pis opened. WVhen the vent-passage P is closed, the vlave J is seated onthe end of the hub and communication between the compressed-air chamberA and the upper end of the cylinder O is interrupted. As soon as thevent-pipe P is opened by raising the valve R in the manner set forth thepressure on the outer side of the pistonvalve J is reduced to much lessthan the pressure on the innerside, which internal pressure is about sixto eight pounds to the squareineh more than atmospheric pressu re, moreor less, and in consequence the piston-valve J is moved toward the headN of the valve-casing, the spring M being compressed. At the same timethe valve 0 is held against the opposite end of the hub F, thus closingthe end of the bore F. The compressed air from the chamber A now passesthrough the duct H into the central bore F of the hub F and from thesame through the duct G into the upper end of the cylinder 0 and forcesdown the piston D. The parts remain in these positions as long as thevent pipe or duct P remains open-that is, as long as the valveR remainsraised. As soon as this valve is closed the pressure is equalized atboth sides of the piston-valve J, compressed air of the same tensionacting on both faces of this pistonvalve,as some compressed airhasfpassed from the duct H through the vent-passage K into thevalve-casing and vent-pipe P and escaped through the latter, this escapeceasing as soon as the valve R is closed. The compressed air now acts onthe inner side of the valve 0 and presses the same outward,whereby thepiston-valve J is seated and the communication between the cylinder 0and the compressed-air chamber A is interrupted. The spring Dimmediately throws the piston D upward, the air from the upper part ofthe cylinder 0 escaping through the duct G and bore F, one end of whichis opened to the atmosphere by the valve 0.

The vent-passage K is made adjustable, so as to prevent a waste ofcompressed air, but still to permit a sufficient quantity to pass intothe vent-pipe P for equalizing the pressure.

Having described my invention, what I claim as new, and desire to secureby Letters Patent, is

1. The combination with a cylinder, piston and piston-rod, of acompressed-air chamber, a valve-casing in communication with thecompressed-air chamber and cylinder, a valve in said casing forcontrolling the passage of compressed air into the cylinder, which valvehas a vent-passage establishing communication between the compressed-airchamber and that part of the valve-casing beyond the valve and a vent inthe valve-casing, and means for antomaticallycontrolling said vent inthe casing substantially as herein shown and described.

2. The combination with a cylinder, piston and piston-rod, of acompressed-air chamber, a valve-casing in communication with thecylinder and com pressed-air chamber, a valve in said casing,controlling the passage of compressed air from the chamber to thecylinder, said valve having a vent for establishing communicationbetween the compressed-air chamber and that part of thevalve-casingbeyond the valve, a vent-tube connected with the casing, avalve controlling said vent-tube and means for automatically operatingsaid valve in the vent-tube,substantially as herein shown and described.

3. The combination with a cylinder, piston and piston-rod, of acompressed-air chamber, a valve-casing in communication with thecompressed-air chamber and the cylinder, a valve in said Valve-casin gand provided with a tubular rod on which the valve is mounted and inwhich rod the said screw is screwed, a vent-tube connected with the valve-casing and means for controlling said vent-tube, substantially asherein shown and described. 4. The combination with a cylinder, a pistonand piston-rod, of acompressed-air chamber, a valve-casing incommunication with the compressed-air chamber and the cylinder, a rodmounted in said casing to move longitudinally in the same, two valves onsaid rod, an apertured hub in the valve-casing, on which hub said valvescan seat and means for varying the pressure on the valves for shiftingthem with the rod to which they are attached, substantially as hereinshown and described.

5. The combination with a cylinder, piston and piston-rod, of acompressed-air chamber, a valve-casing in communication with thecompressed-air chamber and the cylinder, a hub in the said casing andhaving a central bore, a duct extending from said hub-bore to thecylinder, a duct in said hub, extending from the compressed-air chamberto one end of the hub, a rod mounted to move longitudinally through saidhub, valves mounted on said rod at opposite ends of the hub to seat onsaid opposite ends, one valve having a vent for establishingcommunication between the duct extending to the compressedair chamberand said casing, a vent-tube connected with the valve-casing and meansfor controlling said vent-tube, substantially as herein shown anddescribed.

6. The combination with a cylinder, piston and piston-rod, of acompressed-air chamber, a valve-casing in communication with thecompressed-air chamber and cylinder, a central apertured hub in saidvalve-casing, and having a duct connecting the bore of the hub with thecylinder, a rod mounted to move longitudinally through said hub, twovalves on said rod, which seat on the opposite ends of the hub,avent-tube connected with the valvecasing and means for controlling saidventtube, substantially as herein shown and described.

Signed at New York city, in the county of New York and State of NewYork, this 6th day of November, A. D. 1899.

HARRY M. SALYER.

Witnesses:

N. M. FLANNERY, OSCAR F. GUNZ.

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